1
我有一个简单的Java程序，似乎运行良好，直到上传到我的学校的评分系统“WebCat”，我假设它只是运行JUnit。它踢回的错误是：分叉的Java VM异常退出。 JUnit测试？
分叉Java VM异常退出。请注意，报告中的时间不会反映出虚拟机退出前的时间。
我已经研究过这个问题，主要的第一个故障排除步骤似乎是查看转储日志。不幸的是，我不能这样做。考虑到缺乏评分系统的反馈以及缺少编译或运行时错误，我对如何开始排除此故障感到非常失望。
这里是代码，如果任何人都熟悉这个错误，或者至少可以给我一些方向从哪里开始故障排除。非常感激！
import java.io.BufferedReader;
import java.io.File;
import java.io.FileInputStream;
import java.io.InputStreamReader;
import java.util.Scanner;
import java.io.IOException;
class PlayerApp {
public static void showMenu()
{
System.out.println("Player App Menu");
System.out.println("P - Print Report");
System.out.println("A - Add Score");
System.out.println("D - Delete Score");
System.out.println("L - Find Lowest Score");
System.out.println("H - Find Highest Score");
System.out.println("Q - Quit");
}
public static void main(String[] args) throws IOException
{
if (args.length == 0)
{
System.out.println("File name was expected as a run argument.");
System.out.println("Program ending.");
System.exit(0);
}
String fileName = args[0];
Scanner sc = new Scanner(System.in);
String stnew = "";
boolean exit = false;
Player p = null;
double[] scoreList;
File dbFile = new File(fileName);
FileInputStream fis = new FileInputStream(fileName);
InputStreamReader inStream = new InputStreamReader(fis);
BufferedReader stdin = new BufferedReader(inStream);
String name = stdin.readLine();
stnew = stdin.readLine();
int numScore = Integer.parseInt(stnew);
scoreList = new double[numScore];
for (int i = 0; i < numScore; i++)
{
stnew = stdin.readLine();
scoreList[i] = Double.parseDouble(stnew);
}
p = new Player(name, numScore, scoreList);
stdin.close();
System.out.println("File read in and Player object created.");
showMenu();
while (exit == false)
{
System.out.print("\nEnter Code [P, A, D, L, H, or Q]:");
String choice = sc.nextLine().toLowerCase();
if (choice.equals("p"))
{
System.out.println(p.toString());
}
else if (choice.equals("a"))
{
System.out.print(" Score to add: ");
stnew = sc.nextLine();
double scoreIn = Double.parseDouble(stnew);
p.addScore(scoreIn);
}
else if (choice.equals("d"))
{
System.out.print(" Score to delete: ");
stnew = sc.nextLine();
double scoreIn = Double.parseDouble(stnew);
p.deleteScore(scoreIn);
System.out.println(" Score removed.");
}
else if (choice.equals("l"))
{
System.out.println(" Lowest score: " + p.findLowestScore());
}
else if (choice.equals("h"))
{
System.out.println(" Highest score: " + p.findHighestScore());
}
else if (choice.equals("q"))
{
exit = true;
}
}
}
}
休息
import java.text.DecimalFormat;
public class Player {
//Variables
private String name;
private int numOfScores;
private double[] scores = new double[numOfScores];
//Constructor
public Player(String nameIn, int numOfScoresIn, double[] scoresIn) {
name = nameIn;
numOfScores = numOfScoresIn;
scores = scoresIn;
}
//Methods
public String getName() {
return name;
}
public double[] getScores() {
return scores;
}
public int getNumScores() {
return numOfScores;
}
public String toString() {
String res = "";
DecimalFormat twoDForm = new DecimalFormat("#,###.0#");
DecimalFormat twoEForm = new DecimalFormat("0.0");
res += " Player Name: " + name + "\n Scores: ";
for (int i = 0; i < numOfScores; i++)
{
res += twoDForm.format(scores[i]) + " ";
}
res += "\n Average Score: ";
res += twoEForm.format(this.computeAvgScore());
return res;
}
public void addScore(double scoreIn) {
double newScores[] = new double[numOfScores +1 ];
for (int i = 0; i < numOfScores; i++)
{
newScores[i] = scores[i];
}
scores = new double[numOfScores + 1];
for(int i = 0; i < numOfScores; i++)
{
scores[i] = newScores[i];
}
scores[numOfScores] = scoreIn;
numOfScores++;
}
public boolean deleteScore(double scoreIn) {
boolean found = false;
int index = 0;
for (int i = 0; i < numOfScores; i++)
{
if (scores[i] == scoreIn)
{
found = true;
index = i;
}
}
if (found == true)
{
double newScores[] = new double[numOfScores -1 ];
for (int i = 0; i < index; i++)
{
newScores[i] = scores[i];
}
for (int i = index + 1; i < numOfScores; i++)
{
newScores[i - 1] = scores[i];
}
scores = new double[numOfScores - 1];
numOfScores--;
for (int i = 0; i < numOfScores; i++)
{
scores[i] = newScores[i];
}
return true;
}
else
{
return false;
}
}
public void increaseScoresCapacity()
{
scores = new double[numOfScores + 1];
numOfScores++;
}
public double findLowestScore() {
double res = 100.0;
for (int i = 0; i < numOfScores; i++)
{
if (scores[i] < res)
{
res = scores[i];
}
}
return res;
}
public double findHighestScore() {
double res = 0.0;
for (int i = 0; i < numOfScores; i++)
{
if (scores[i] > res)
{
res = scores[i];
}
}
return res;
}
public double computeAvgScore() {
double res = 0.0;
if (numOfScores > 0) {
for (int i = 0; i < numOfScores; i++)
{
res += scores[i];
}
return res/(double)(numOfScores);
}
else {
//res = 0.0;
return res;
}
}
}
好悲伤！承认我浪费在这个小问题上的时间令人尴尬。你的时间非常感谢！ – user2092509 2013-03-18 03:16:59
这是我在现实生活中可能遇到的问题，还是仅仅是一个自动评分问题？似乎退出该计划是我在该计划的关键时刻想要做的事情？ – user2092509 2013-03-18 03:18:19
当你在现实生活中调用'exit（）'时，你确实必须小心。如果你自己写了'main（）'，那就去做吧，因为你已经掌握了。另一方面，如果你正在写一个与扫描器对话的库（仅仅是一个例子），那么该库永远不会更好，因为你不知道什么类型的程序可能会被调用'exit（）'给你打电话。如果我使用你的图书馆，并且我的程序神秘地退出，我将不会高兴！ – 2013-03-18 03:21:56